Because of their high efficiency and long life, light emitting diodes (LEDs) are expected to be used as the next-generation of light sources in various products, for example, well-known conventional lighting apparatuses such as a fluorescent light and an incandescent light bulb. Thus, research and development for LED-based lighting light sources are being undertaken. At the same time, development for drive circuits for driving LEDs is also being undertaken (see, Patent Literature (PTL) 1 for example).